The phrase "endlessly obsessed" is correct and usable in written English.
You can use it to express an intense focus on something. For example, "She was endlessly obsessed with finding the perfect dress for the wedding."
It's a subject that endlessly obsesses us".
Herein lies the greatest irony: in the office, we endlessly obsess over ROI; in the gym, however, we pound away on the treadmill for hours and hours (probably while thinking about none other than ROI).
What will the main Silly Season story become, for pundits to endlessly obsess over this August?
One that they research endlessly and obsess over its admission requirements.
If we obsessed, endlessly, about our partners and had sex with them multiple times a day — every day — we would not be very productive at work or attentive to our children, our friends or our health.
The tale of Lord Lucan's disappearance is one of the most fascinating and endlessly obsessed-over crime events in modern British history.
It may seem odd to complain about a lack of interest in our molecular nature because people seem to be endlessly fascinated – if not obsessed – by DNA, one of the most famous biological molecules of all time.
"They become preoccupied with events that have passed — obsessing endlessly on a possible wrong answer or a missed opportunity.
Its sufferers often become obsessed with specific topics, talking endlessly about them with stunning expertise; they have problems socializing, make inappropriate comments and avoid eye contact.
Obsessed with her own death, Dolly frets endlessly about the size and color of her coffin and what she should wear to her grave.
